JPS6337335Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a webbing lock device that is used in a seat belt device for protecting occupants in vehicle emergencies and locks occupant restraining webbing when necessary. The present invention relates to a webbing lock device that locks webbing to restrain an occupant.

A webbing lock device has been proposed that directly clamps the middle portion of the webbing for restraining an occupant of a seat belt device in the event of a vehicle emergency to restrain the occupant by the webbing. In the event of a vehicle emergency, this webbing lock device operates a pair of clamping members using the tension of the webbing to directly clamp the middle portion of the webbing. Therefore, no large tension is applied to the webbing that is wound in layers around the winding shaft.
Since there is no problem in which the webbing of the layered winding section is stretched out due to tightening, the performance of restraining the occupant is improved.

However, in this webbing lock device, the corresponding surfaces of the pair of clamping members are wave-shaped to increase the frictional force between them and the webbing, which causes an error in the clamping force. In other words, in order to lock the webbing with a uniform clamping force from the winding shaft side to the occupant restraint part side, the corresponding waveform shapes formed on the surfaces of the pair of clamping members require extremely high precision waveform shapes. . Furthermore, due to errors during assembly, it may not be possible to have a tight clamping force when locking, resulting in variations in locking performance, and the clamping force may become large in some areas, potentially damaging the webbing. There is. Also,
Japanese Utility Model Application Publication No. 55-126853 and Japanese Utility Model Application Publication No. 55-116648 disclose a device that clamps the middle part of webbing by a wave-shaped protrusion or a wave-like unevenness clamping member, but the above-mentioned webbing lock device Similarly, the locking performance may vary due to errors during installation, and there is a risk that the webbing may be locally damaged.

In consideration of the above facts, the purpose of the present invention is to provide a webbing lock device that does not require high-precision manufacturing of the clamping member, is easy to manufacture and assemble, and can reliably obtain a uniform locking state. .

The webbing lock device according to the present invention clamps the intermediate part of the webbing for restraining an occupant between the fixed clamping members in the event of a vehicle emergency, and the movable clamping member that prevents longitudinal movement of the webbing is rotatable in opposition to the fixed clamping member. In the provided webbing lock device, the fixed clamping member has a flat holding part on the winding shaft side and a convex non-clamping curved part on the occupant restraint side, and the movable member has a shape corresponding to each shape of the fixed clamping member. Planar holding parts that face each other and hold the webbing in the thickness direction;
It is configured to include a U-shaped recess into which the convex curved surface enters, and a convex portion that bends the webbing and presses it along the convex curved surface to engage it.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a webbing retractor 10 incorporating a webbing lock device according to the present invention. In this webbing retractor 10, a frame 12 is fixed to a vehicle body with mounting bolts 14.

A pair of leg plates 18 are provided extending parallel to each other from both sides of the frame 12 (however, one leg plate 18 is not shown in FIG. 1). A take-up shaft 22 is pivotally supported, and one end of an occupant restraining webbing 24 is wound up in layers. This winding shaft 22 is biased in the winding direction of the webbing 24 (in the direction of arrow A in FIG. 1) by the biasing force of a mainspring spring (not shown).
The other end (not shown) of the webbing 24 is pulled out of the take-up device 10 and reaches the occupant restraint section.

A pair of ratchet wheels 26 are fixed to the winding shaft 22 so as to rotate together with the winding shaft 22, and correspond to a ball 28 tiltably supported on the parallel leg plate 18. This ball 28 is actuated by an acceleration sensor (not shown) using a pendulum or the like, and engages with the latchet wheel 26 to prevent the latchet wheel 26 and the take-up shaft 22 from unwinding the webbing (in the direction opposite to the direction of arrow A). .

A support shaft 30 is supported at the bottom of the parallel leg plate 18, and one end of a pair of arms 32 is supported at each end (however, only one arm 32 is shown in FIG. 1).
(The illustration of the rollers 34 is omitted.) A roller 34 is journalled on the other end of each of the arms 32, around which the middle portion of the webbing 24 is wound and guided.

The webbing between the roller 34 and the winding shaft 22 is connected to a roller 38 which is pivotally supported by a pin 36 to the leg plate 18.
It is wrapped around the body.

A fixed clamping member 40 is provided on one side of the webbing 24 between the rollers 34 and 38 and on the opposite side of the arm 32.
is fixed to the leg plate 18. The fixed holding member 40 is composed of a base plate 42 and a lock plate 44 fixed to the outer periphery of the base plate 42 and corresponding to the webbing intermediate portion, and both longitudinal ends of the base plate 42 are fixed to the leg plate 18.

Corresponding to this fixed clamping member 40, rollers 34,
A movable clamping member 46 is provided on the opposite side of the webbing 24 between the webbings 38 and 38.

This movable clamping member 46 is connected to a base plate 48 fixed to the arm 32 and the base plate 48
The lock plate 50 is fixed to the webbing 24 and corresponds to the webbing 24.

The fixed clamping member 40 and the movable clamping member 46 are
As shown in the figure, when a vehicle is running, an appropriate gap is formed between the two so that the webbing 24 can freely pass through. That is, the arm 32 is biased clockwise in FIG. 1 by a tension coil spring 52 interposed between the arm 32 and the leg plate 18, and is stopped by coming into contact with a stopper 54 fixed to the leg plate 18.

However, if the tension of the webbing exceeding a predetermined value is transmitted to the arm 32 via the roller 34, the arm 32
2 rotates in the counterclockwise direction in FIG. 1 against the biasing force of the tension coil spring 52, and as shown in FIG. It is designed to sandwich the middle part.

To explain the shapes of the fixed clamping member 40 and the movable clamping member 46 in detail, the fixed clamping member 40 and the movable clamping member 46 are provided with planar clamping parts 56 and 58, respectively. These planar holding parts 56,5
As shown in FIG. 2, the webbing 8 is designed to clamp the middle portion of the webbing 24 in the thickness direction in the event of a vehicle emergency to prevent the webbing from moving in the longitudinal direction.

A convex curved surface 60 is continuously provided on the planar holding portion 56 along the longitudinal direction of the webbing and closer to the occupant restraint portion. This convex curved surface 60 corresponds to the concave portion 62 of the movable clamping member 46. In addition, the movable clamping member 46
A convex portion 64 is provided closer to the occupant restraint portion than the concave portion 62, and this allows the movable clamping member 46 to move between the planar clamping portion 58, the concave portion 62, and the convex portion 6.
4 has a substantially U-shape, and the recess 6
The convex curved surface 60 can enter into the inside of the 2. As a result, in the event of a vehicle emergency, the webbing between the roller 34 and the flat clamping part 56 is bent by the convex curved surface 60 and the convex part 64, as shown in FIG. 2, but is not clamped by these. The structure is such that the webbing 24 pressed along the curved surface of the convex curved surface 60 engages with the convex curved surface 60, and the tension of the webbing 24 is reduced by the frictional force generated uniformly in the longitudinal direction. It's summery.

Next, the operation of this embodiment will be described. By unwinding the webbing 24 from the take-up shaft 22 against the winding force, the occupant can attach an end portion (not shown) of the webbing 24.

Here, the occupant can unwind the required amount of webbing 24 from the take-up shaft while the vehicle is normally running, and can arbitrarily change the driving posture.

Next, in the event of an emergency situation such as a vehicle collision, an acceleration sensor (not shown) will activate the pole 2.
8 meshes with the ratchet wheel 26 and the winding shaft 22
suddenly stop the webbing unwinding rotation.

On the other hand, the webbing 24 receives the collision inertia of the occupant and generates a large tension, and this tension is transmitted to the roller 34, causing the arm 32 to rotate counterclockwise in FIG. 1 and reach the state shown in FIG. 2. In the state shown in FIG.
approaches the planar clamping portion 56 of the fixed clamping member 40 and clamps the intermediate portion of the webbing 24 between them in the thickness direction. Further, since the concave portion 62 and the convex portion 64 of the movable clamping member 46 bend the webbing between the convex curved surface 60 of the fixed clamping member 40, these convex curved surfaces 60
and the webbing 2 due to frictional force with the convex portion 64.
The tension in the middle part of 4 is attenuated. The webbing 24 having this attenuated tension is held at the planar holding portion 56,
Since the webbing 24 is held between the flat holding parts 56 and 58, the webbing 24 is reliably locked between the planar holding parts 56 and 58, and its longitudinal movement is stopped. In addition, since the tension has already been reduced to some extent in the planar clamping parts 56 and 58, even if a large clamping force is applied in the thickness direction, the change in the tension of the webbing is relatively small, so the webbing will not be damaged. .

Since the webbing is reliably locked between the flat clamping parts 56 and 58 in this way, the flat clamping part 5
Since no large tension is applied to the webbing between the webbing 6, 58 and the take-up shaft 22 and the winding is not tightened, the occupant wearing the webbing end (not shown) is securely restrained and safety is guaranteed. Ru.

Next, FIG. 3 shows a second embodiment of the present invention, in which a bar 66 with a rectangular cross section and a pin 68 are provided in place of the fixed clamping member 40 in the previous embodiment. The rod 66 and the pin 68 have their longitudinal ends fixed to the leg plate 18, and their surfaces constitute the planar holding portion 56 and the convex curved surface 60.

Further, a bar 70 having a rectangular cross section and a pin 72 are fixed to the arm 32, the surface of the bar 70 constitutes a flat holding part 58, and the pin 72 is attached to a convex part 64.
The gap between the bar 70 and the pin 72 substantially forms the recess 62 in the embodiment described above.

Therefore, in this embodiment, the fixed clamping member and the movable clamping member can be constructed by simply providing a bar and a pin, and the same effects as in the previous embodiment can be obtained.

As explained above, the webbing lock device according to the present invention has a planar clamping part and a non-clamping curved part as clamping members, so it is easy to manufacture and does not require high-precision machining and assembly, and the webbing has a convex curved surface. Since the webbing is pressed and engaged along the webbing, a uniform frictional force acts and the webbing is not locally damaged and the webbing tension is reliably reduced. It has an excellent effect of reliably preventing directional movement and improving the performance of restraining the occupant.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the webbing lock device according to the present invention in a state during normal vehicle running, Fig. 2 is an operating diagram of Fig. 1, and Fig. 3 is an operating state of a second embodiment of the invention. FIG. DESCRIPTION OF SYMBOLS 10... Webbing winding device, 32... Arm, 40... Fixed holding member, 46... Movable holding member, 56, 58... Planar holding part, 60... Convex curved surface, 62... Concave part, 64... ...Protrusion, 66, 70...
...bar, 68, 72...pin.

Claims (1)

[Scope of utility model registration request] A webbing lock device which clamps an intermediate part of webbing for restraining an occupant between fixed clamping members in the event of a vehicle emergency, and includes a movable clamping member rotatably provided opposite to the fixed clamping member to prevent longitudinal movement of the webbing. In this, the fixed clamping member has a planar clamping part on the winding shaft side and a non-clamping curved part with a convex curve on the occupant restraint part side, and the movable clamping member has a shape corresponding to each shape of the fixed clamping member. a flat holding part that faces and holds the webbing in the thickness direction;
A webbing lock device comprising: a U-shaped recess into which the convex curved surface enters; and a convex portion that bends the webbing to press and engage the webbing along the convex curve.